02141nas a2200493   4500000000100000008004100001260001500042100002600057700002400083700002100107700001300128700001500141700001600156700002300172700001600195700001800211700002600229700001800255700002000273700002100293700002000314700001500334700001700349700002000366700001600386700002500402700001400427700001900441700001200460700002500472700001500497700001500512700001300527700001600540700002200556700001400578700001500592700002100607245008800628856005600716300001300772490000800785520085400793       2024                            d  c2024-05-101 aAlexander Shapson-Coe1 aMichał Januszewski1 aDaniel R. Berger1 aArt Pope1 aYuelong Wu1 aTim Blakely1 aRichard L. Schalek1 aPeter H. Li1 aShuohong Wang1 aJeremy Maitin-Shepard1 aNeha Karlupia1 aSven Dorkenwald1 aEvelina Sjostedt1 aLaramie Leavitt1 aDongil Lee1 aJakob Troidl1 aForrest Collman1 aLuke Bailey1 aAngerica Fitzmaurice1 aRohin Kar1 aBenjamin Field1 aHank Wu1 aJulian Wagner-Carena1 aDavid Aley1 aJoanna Lau1 aZudi Lin1 aDonglai Wei1 aHanspeter Pfister1 aAdi Peleg1 aViren Jain1 aJeff W. Lichtman00aA petavoxel fragment of human cerebral cortex reconstructed at nanoscale resolution  uhttps://www.science.org/doi/10.1126/science.adk4858  aeadk48580 v3843 aTo fully understand how the human brain works, knowledge of its structure at high resolution is needed. Presented here is a computationally intensive reconstruction of the ultrastructure of a cubic millimeter of human temporal cortex that was surgically removed to gain access to an underlying epileptic focus. It contains about 57,000 cells, about 230 millimeters of blood vessels, and about 150 million synapses and comprises 1.4 petabytes. Our analysis showed that glia outnumber neurons 2:1, oligodendrocytes were the most common cell, deep layer excitatory neurons could be classified on the basis of dendritic orientation, and among thousands of weak connections to each neuron, there exist rare powerful axonal inputs of up to 50 synapses. Further studies using this resource may bring valuable insights into the mysteries of the human brain.